Search results for "Cardiology"
showing 10 items of 6064 documents
Cardiovascular magnetic resonance-derived aortic compliance, distensibility and pulse wave velocity at rest and during a supine bicycle exercise in y…
2014
Background Purpose: Risk of aortic rupture is evaluated based on the vessel diameter; this parameter is probably insufficient. In vivo evaluation of biomechanical property of the aortic tissue might be of interest to discriminate between normal and altered aortic tissue (A Lalande et al, JMRI 2008). The purpose of this study was to describe a technique to measure regional aortic compliance (AC), aortic distensibility (AD) and aortic stiffness with 1.5 T MRI in young individuals under resting conditions and during supine bicycle exercise.
Information domain approach to the investigation of cardio-vascular, cardio-pulmonary, and vasculo-pulmonary causal couplings
2011
The physiological mechanisms related to cardio-vascular (CV), cardio-pulmonary (CP), and vasculo-pulmonary (VP) regulation may be probed through multivariate time series analysis tools. This study applied an information domain approach for the evaluation of non-linear causality to the beat-to-beat variability series of heart period (t), systolic arterial pressure (s), and respiration (r) measured during tilt testing and paced breathing (PB) protocols. The approach quantifies the causal coupling from the series i to the series j (C(ij)) as the amount of information flowing from i to j. A measure of directionality is also obtained as the difference between two reciprocal causal couplings (D(i…
Arrhythmieprofil und Herzfrequenz bei Hyperthyreose
2008
Arrhythmia profiles and heart rates, obtained by 24-hour ECG monitoring, were analysed in 48 patients with hyperthyroidism before (T3 level: 331 +/- 108 ng/100 ml, heart rate: 95 +/- 13/min), during (T3 level: 202 +/- 98 ng/100 ml, heart rate: 85 +/- 11/min) and after (T3 level: 149 +/- 41 ng/100 ml, heart rate: 79 +/- 9/min) antithyroid treatment. 50 persons in whom organic heart disease has been excluded by invasive and noninvasive tests served as controls. Only 6% of patients had repetitive ventricular arrhythmias (Lown group IV) before treatment (controls: 4%; P greater than 0.05). Supraventricular extrasystoles were common both before and after treatment (P less than 0.001), especially…
Intracardiac Cardioversion for Ablation of the Atrioventricular Conduction System in Patients with Drug Resistant Atrial Flutter
1983
The technique of intracardiac cardioversion for the ablation of the atrioventricular conduction system was used in three male patients (65, 53 and 57 years of age) with atrial flutter unresponsive to medical management. In the first patient a DC current of 80 J was applied while the other patients required 300 and 400 J respectively. In the first patient a transient third degree AVblock was induced enabling the ventricular rate to be easily controlled with drugs. This patient died 5 months later of resistant congestive heart failure. Autopsy revealed no gross evidence of myocardial damage in the tricuspid valve area or in the interventricular septum. In the other two patients a permanent th…
Retrograde recanalization of an in-stent ostial chronically occluded right coronary artery
2010
We describe a case of a chronic proximal in-stent CTO extending up to the ostium of a right coronary artery where successful achievement of guidewire passage through the CTO was performed with a retrograde approach. Guidewire trapping into the right guiding catheter was performed thereafter and procedure was completed by retrograde balloon crossing and antegrade stenting. © 2009 Elsevier Ireland Ltd.
Choice of the operative approach in two cardiosurgical patients assisted by preoperative computed tomography: Case Report
1988
The perioperative course of two patients is exemplified to demonstrate the significance of the preoperative thoracic computed tomography for the selection of a proper surgical approach.
Transmission of arterial oxygen partial pressure oscillations to the cerebral microcirculation in a porcine model of acute lung injury caused by cycl…
2013
Cyclic recruitment and derecruitment (R/D) play a key role in the pathomechanism of acute lung injury (ALI) leading to respiration-dependent oscillations of arterial partial pressure of oxygen (Pa(O(2))). These Pa(O(2)) oscillations could also be forwarded to the cerebral microcirculation.In 12 pigs, partial pressure of oxygen was measured in the thoracic aorta (Pa(O(2))) and subcortical cerebral tissue (Pbr(O(2))). Cerebral cortical haemoglobin oxygen saturation (Sbr(O(2))), cerebral blood flow (CBF), and peripheral haemoglobin saturation (Sp(O(2))) were assessed by spectroscopy and laser Doppler flowmetry. Measurements at different fractions of inspired oxygen (F(I(O(2)))) were performed …
Microvascular obstruction in the right ventricle in reperfused anterior myocardial infarction. Macroscopic and pathologic evidence in a swine model.
2013
article i nfo Introduction: Data on right ventricular (RV) involvement in anterior myocardial infarction are scarce. The presence of RV microvascular obstruction (MVO) in this context has not been analyzed yet. The aim of the present study was to characterize the presence of MVO in the RV in a controlled experimental swine model of reperfused anterior myocardial infarction. Materials and Methods: Left anterior descending (LAD) artery-perfused area (thioflavin-S staining after selective infusioninLADartery),infarctsize(lackof triphenyltetrazolium-chloride staining) andMVO (lack of thioflavin-S staininginthe core oftheinfarctedarea) inthe RVwere studied.A quantitative(%of theventricularvolume…
Magnetic resonance microscopy and correlative histopathology of the infarcted heart
2019
Altres ajuts:The present study was supported by the EU Joint Programming Initiative 'A Healthy Diet for a Healthy Life' (JPI HDHL INTIMIC-085), Generalitat Valenciana (GV/2018/116), INCLIVA and Universitat de Valencia (program VLC-BIOCLINIC 20-nanomIRM-2016A). Delayed enhancement cardiovascular magnetic resonance (MR) is the gold-standard for non-invasive assessment after myocardial infarction (MI). MR microscopy (MRM) provides a level of detail comparable to the macro objective of light microscopy. We used MRM and correlative histopathology to identify infarct and remote tissue in contrast agent-free multi-sequence MRM in swine MI hearts. One control group (n = 3 swine) and two experimenta…
In vitro comparison of platinum-iridium and gold tip electrodes: lesion depth in 4 mm, 8 mm, and irrigated-tip radiofrequency ablation catheters
2009
Aims We compared a newly developed irrigated gold tip electrode ablation catheter and a gold tip 4 and 8 mm catheter with the corresponding platinum–iridium (Pt) tip catheters in an in vitro setting. Methods and results In a flow chamber simulating physiological flow conditions, radiofrequency catheter ablation was performed on tissue samples of porcine endomyocardium and liver. Lesion depth, energy and temperature delivery, and popping frequency were determined. Two hundred and fifty-three ablations were conducted. Four and eight millimetre, gold tip electrode catheters produced significantly deeper lesions compared with the Pt tip electrode (liver 4 mm: 4.67 ± 1.7 vs. 2.9 ± 1.0 mm, P < 0.…